doc: explain http2 aborted event callback

Line added in the description of http2 aborted event
that it's listener does not expect any arguments.

Refs: nodejs/help#877
PR-URL: #30179
Reviewed-By: Gireesh Punathil <gpunathi@in.ibm.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

doc/api/http2.md

@@ -938,6 +938,7 @@ added: v8.4.0
 
 The `'aborted'` event is emitted whenever a `Http2Stream` instance is
 abnormally aborted in mid-communication.
+Its listener does not expect any arguments.
 
 The `'aborted'` event will only be emitted if the `Http2Stream` writable side
 has not been ended.